Frontier launched its twice-a-day flights between Milwaukee and Manistee in April, but they will end on March 8, a victim of restructuring aimed at cutting costs.

“Given current and expected future high fuel prices, Frontier can no longer economically continue to operate this service,” spokesman Peter Kowalchuk said Tuesday. “After a thorough analysis of our routes, Frontier has similarly reduced and/or eliminated small regional jet flying in a number of other markets as well.”

Kowalchuk said several cuts and eliminations will start Nov. 1, mostly in Milwaukee, but Kansas City and Denver will see changes, too.

“Frontier will reduce daily departures at Milwaukee from 67 to 45 flights,” he said.

The routes that will be suspended are mostly operated by regional jets with 37 or 50 seats, which Frontier analysis shows to be uncompetitive, Kowalchuk said.

“We have attributed about $25 million in losses to these small-jet, short-haul routes in the first half of 2011 alone,” he said. “And, as we enter the slowest six months of the year, we have to adjust the scale and scope of our business so we can return Frontier to profitability and improve the financial performance of our Milwaukee operation.”